Research On The Influence Of Rail Transit On The Compact Development And Economic Efficiency Of Urban Agglomeration

As a kind of urban sustainable development theory,compact city theory has been widely studies and implemented in wested countries,such as the United States,Europe and Australia.However,with the rapid advance of urbanization in China,whether the theory of compact development can guide the construction of new urbanization in China and provide a new type of urbanization for our country in view of the problems such as the expansion of urban land,the low economic efficiency of cities and the slow development of urban agglomeration.Is the compact intensive development model an ideal choice for the development of urban agglomeration?What is the mechanism of rail transit network in the compact development of city clusters?How to make full use of its support to the compact development of city clusters?Based on these questions,this article has done the following research work:(1)The theoretical analysis and compactness measure of urban agglomeration.Based on the theory of compact development theory,the agglomeration economy,urban spatial interaction theory,etc.,the concept and connotation of compact urban agglomeration is defined comprehensively and systematically.The factors influencing the compact development of urban agglomeration in China are discussed,and from the macro,meso and micro level analysis of the internal driving force and realization way of compact development of urban agglomeration.On this basis,construct the model to measure the compactness of the ten urban agglomeration in China from four aspects:industry compactness,space compactness,traffic compactness and capital compactness.The results show that China's top ten urban agglomerations comprehensive compact degree of all present the overall upward trend from 2001 to 2013.(2)The economic efficiency of urban agglomeration compact development.This paper analyzes the mechanism of urban agglomeration compact development on the economic efficiency.First,the economic efficiency of the ten urban agglomerations in China is measured by the stochastic frontier method(SFA).The results show that the economic efficiency of the ten urban agglomerations in China from 2001 to 2013 increase gradually and the economic efficiency in the eastern coastal areas is significantly higher than that in the central and western regions.Based on the Cobb-Douglas production function,the urban agglomeration compactness-economic efficiency model is constructed to explore the relationship between urban compactness and its economic efficiency.In the fixed effect model,the urban cluster compactness and economic efficiency show significant nonlinear relationship.With the increase of the compactness of the urban agglomeration,the economic efficiency gradually increased until reached the maximum critical point,and the continued increase of the compactness of urban agglomeration would lead to the decline of economic efficiency.Therefore,the compact development of urban agglomeration has a certain limit,too high degree of compact urban agglomeration is not conducive to the sustained and healthy development of urban agglomeration.(3)The internal mechanism and network efficiency evaluation of rail transit network.As the backbone and stent of urban agglomeration development,rail transportation plays an important supporting role in the compact development of urban agglomeration.The rail transit network has a significant network economic effect,and its micro-mechanism is the network benefits from the demand side of the passenger and the freight,including the benefits of saving passengers in transit time,reducing fatigue,improving the productivity of labor and so on;its macro-mechanism includes the promotion of accessibility of the spatial economic link effect,the optimization effect of the industrial structure,and the effect of narrowing the regional gap.The rail transportation network has the characteristics of threshold,so it is necessary to maximize the network economic effect when the network is formed.On this basis,using DEA analysis method to estimate the efficiency of the ten city rail transportation network in China group,and the Malmquist index model is used to study the ten city groups of our country from 2001 to 2013.(4)The spatial and temporal effect of the compact development of urban agglomeration.Review the economic attibutes of rail transit network from two basic dimensions of space and time,and analyze the impact of rail transit network on the evolution of urban agglomeration spatial structure form.It is concluded that different urban rail transit network model corresponds to the different urban agglomeration spatial form;Rail transit networks can promote urban agglomeration spatial structure form,and the rail transit network optimization shortens the time distance between cities,reduces the cost of production factor flow.Residents and industries tend to find the optimal location in urban agglomeration wider diffusion and agglomeration,which inevitably leads to further perfect and development of the urban agglomeration spatial structure,eventually to promote the formation of urban agglomeration network spatial structure.(5)The agglomeration effect of rail transit network on compact development of urban agglomeration.We analyze the influence mechanism of rail transit network on the compact development of urban agglomeration from two angles of traffic cost and accessibility.Firstly,this paper analyzes the impact of rail traffic network on urban agglomeration economy under the restriction of transport cost through a simple theoretical model,and emphatically analyzes the agglomeration effect of rail transit nodes and the city effect of factor flow.Secondly,based on accessibility,we analyzed the mechanism of rail transit network on the enterprises and residents' location selection,urban agglomeration industry labor division of work,and the urbanization and industrialization development of the urban agglomeration.(6)The empirical analysis of rail transit network on urban agglomeration compact development and its economy efficiency.Through the construction of rail transit network-urban agglomeration compactness model and rail transit network-urban agglomeration compactness-productivity model,we used the least squares method and panel GMM(GMM)to estimate the relationshipsbetween rail transit network and urban agglomeration compactness and its economic efficiency.The results show that:firstly,the traffic variable has a significant positive effect on the compactness of urban agglomeration,but this effect has time lag.This means that by further improving the rail transit infrastructure and services to guide and promote the compact development of the urban agglomeration is effective,the increase in the size and the density of the rail transit network has a positive role in promoting urban agglomeration compact development.Secondly,the rail transit has a significant positive impact on the economic efficiency of the urban agglomeration.The rail transit not only has a direct impact,but also has some indirect affect.The effect of lagging explanatory variables on urban productivity changes is small,but it is significant,which shows that the impact of rail transit and urban agglomeration on the change of urban agglomeration productivity is lagging behind.Through the above theoretical research and empirical research results,two conclusions can be drawn:(1)The compact development of urban agglomeration can effectively promote the economic efficiency of the urban agglomeration,but the compact development has a certain limit,and the excessive compactness of the urban agglomeration is not conducive to the sustainable and healthy development of the urban agglomeration.Therefore,the compact and intensive development model should be a scientific choice for the development of urban agglomerations in China.(2)The rail transit network has a significant positive impact on the compact development and economic efficiency of urban agglomeration.The development of the rail transit network is not only an essential element of the urban agglomeration compact development,but also an important force to support the compact development of the urban agglomeration.Rail transport has to form network for overcoming its "threshold"to achieve a strong support for the compact development of urban agglomeration.Therefore,it is necessary to promote the development of rail transit network,maximize its network economic effect,and give full play to its support for the compact development of urban agglomeration.Finally,this paper puts forward some suggestions to promote the compact development of urban agglomeration from four aspects.Meanwhile,some positive measures are also proposed onthe rail traffic to support the compact development of urban agglomeration.